1. Field of the Invention
The present invention relates to the field of automated packaging equipment and in particular relates to bag filling equipment used to fill large flexible bags with fluidic, semifluidic or mixtures of solid and fluidic foodstuffs.
2. Description of the Prior Art
Generally, institutional quantities of foodstuff are packaged in conventional, rigid cans. Flexible bags have been used for foodstuff primarily for individual, consumer quantities, such as individual servings of ketchup, mayonnaise or other condiments. As a result, foodstuff packaged in pouch or smaller size bags are filled and sealed by machines which can handle only those bags designed for small weights, and volumes. This type of food packing machinery is totally inadequate for filling and sealing bags for institutional customers, which bags may contain thirty pounds or more of foodstuff. Additionally, bags large enough to contain thirty pounds of foodstuff necessarily include a large sealing area and usually entrap a relatively large volume of air. Any defect or wrinkle in the seal, which defect or wrinkle may be exaggerated by the large weight of foodstuff contained within the bag or any large volume of air left within the bag, can easily cause rapid deterioration and/or spoilage of the foodstuff. The resulting loss in an institutional size bag can be a significant loss. Therefore, unless the seal is made and the air removed from the bag with a high degree of reliability, a flexible bag will be unsuitable for institutional quantities of foodstuff. For this reason large size, flexible bags have been used only with specialized and expensive spouts or seal mechanisms.
What is needed then is an apparatus for filling and sealing large flexible bags without special sealing mechanisms such that the seal is perfectly formed with a high degree of reliability and such that a means is devised to remove air entrapped within the bag.